Early elevation of cardiac troponin I is predictive of short-term outcome in neonates and infants with coronary anomalies or reduced ventricular mass undergoing cardiac surgery

Objective: The present study aimed to assess the usefulness of routine monitoring of cardiac troponin I concentrations within 24 hours of surgery (cTn-I<24h) in neonates and infants undergoing cardiac surgery. Methods: The added predictive ability of a high peak cTn-I<24h (within the upper quintile per procedure) for a composite outcome, including 30-day mortality and severe morbidity, was assessed retrospectively. The predicted risk for the composite outcome was estimated from a logistic regression model including preoperative and intraoperative variables. Adding a high peak cTn-I<24h to the risk model resulted in reclassification of the predicted risk. It also allowed quantification of the improvement in reclassification and discrimination by the difference between c-indexes, the Net Reclassification and the Integrated Discrimination Indexes (NRI and IDI). Results: Overall, 1023 consecutive patients were included. Adding a high peak cTn-I<24h to the model resulted in no improvement in reclassification or discrimination in the overall population (difference between c-indexes: 0.011 [-0.004 to 0.029], NRI=0.06, P=.22, IDI=0.02, P=.06), except in a subgroup of patients undergoing the arterial switch operation with or without ventricular septal defect closure and/or aortic arc repair, anomalous origin of the left coronary artery from the pulmonary artery repair, truncus arteriosus repair, Norwood procedure, and Sano modification, in whom NRI - 0.23 (P - .005) and IDI - 0.05 (P<.001). Conclusions: Patients with coronary anomalies and patients with reduced ventricular mass should benefit from the routine monitoring of cTn-I concentrations after surgery for congenital cardiac disease. (J Thorac Cardiovasc Surg 2012;144:1436-44)